1. Field of the Invention
This invention relates to novel 6-quinazolinesulfonyl derivatives which possess a relaxatory action for vascular smooth muscle and are useful as a vasodilator and a hypotensor, and a process for the preparation thereof.
2. Summary of the Invention
According to the present invention in one embodiment there is provided a 6-quinazolinesulfonyl derivative of Formula (I): ##STR4## wherein R.sub.1 is a hydrogen atom or a C.sub.1-12 alkyl group;
R.sub.2 is a hydrogen atom, a C.sub.1-12 alkyl group, a C.sub.4-10 cycloalkyl group, an aryl group or an aralkyl group; and PA1 R.sub.1 and R.sub.2 may be linked directly or through an oxygen atom to form a 5- to 7-membered heterocyclic ring together with the adjacent nitrogen atom; and PA1 R.sub.3 is a ##STR5## group wherein R.sub.4 is a C.sub.1-8 alkyl group; a --NH(CH.sub.2).sub.n NH.sub.2 group wherein n is an integer of 2 to 10; or a ##STR6## group; and the pharmaceutically acceptable acid addition salt thereof. PA1 R.sub.2 is a hydrogen atom, a C.sub.1-12 alkyl group, a C.sub.4-10 cycloalkyl group, an aryl group or an aralkyl group; and PA1 R.sub.1 and R.sub.2 may be linked directly or through an oxygen atom to form a 5- to 7-membered heterocyclic ring together with the adjacent nitrogen atom; and PA1 X is a halogen atom such as chlorine atom and a bromine atom, with a compound of Formula (III); EQU R.sub.3 H (III) PA1 R.sub.3 is a ##STR11## group wherein R.sub.4 is a C.sub.1-8 alkyl group; a --HN(CH.sub.2).sub.n NH.sub.2 group wherein n is an integer of 2 to 10; or a ##STR12## group, in accordance with the following equation: ##STR13## PA1 R.sub.2 is a hydrogen atom, a C.sub.1-12 alkyl group, a C.sub.4-10 cycloalkyl group, an aryl group or an aralkyl group; and PA1 R.sub.1 and R.sub.2 may be linked directly or through an oxygen atom to form a 5- to 7-membered heterocyclic ring together with the adjacent nitrogen atom,
The present invention in another embodiment provides a process of preparing the above described 6-quinazolinesulfonyl derivative.